The present invention relates to an electronic sensor system for monitoring a window, door or other opening associated with a vehicle or vehicle interior, and in particular a system for mounting, aiming, and/or packaging such a sensor system.
In recent years, electronic sensors have not been utilized for obstacle or intrusion detection in vehicle window systems because of complexity and mounting limitations. Typically, obstacle detection has been based on limit switches, window motor characteristics, or ultrasonic monitoring signals that do not have precise mounting or alignment requirements. Small variations in detection system mounting do not significantly effect the performance of these sensor systems. The variations in trim components and installer techniques obviates the use of potentially more sensitive and thus accurate monitoring systems which are subject to performance degradation as a result of misalignment with respect to an ideal mounting configuration.
So-called tolerance stack-up results due to the variability in the physical relationship between a lens to emitters or detectors of an obstacle detection system, emitters or detectors to a circuit board on which they are mounted, the circuit board to the respective housing, the housing to vehicle trim and/or the respective door panel, and vehicle trim and/or the door panel to the door sheet metal. Variations from vehicle to vehicle, door to door, in system installation techniques within the vehicle factory, and in system installation techniques by after-market installers can all add to the tolerance stack-up problem.
The present invention provides an obstacle detection system which includes a monitoring sensor system and a mounting system. In a first embodiment, the obstacle detection system is adapted for use in a vehicular setting. The mounting system presently disclosed allows an installer to make aiming adjustments, in the factory or field, to account for the tolerance stack-up problems described above. The system includes a housing for mounting the monitoring sensor system to minimize cross-talk and interference between the transmitter and receiver sections, to limit sensor system movement based on vehicle component and factory installation variations, and to enable gross and fine aiming to accommodate field programmability.
In a preferred embodiment of the invention, a circuit board is disposed within a cradle assembly which, in turn, is mounted in or integral to the housing to position the obstacle detection sensor in proximity with the target structure or region of the vehicle. The cradle in one embodiment is an enclosure for the circuit board, fabricated from a resilient material such as plastic. Importantly, the cradle does not obstruct or interfere with the operation of the transmitter or receiver associated with the sensor disposed on the circuit board. The cradle may facilitate sensor removal and replacement without requiring the removal of the housing. Thus, once the housing is properly aligned relative to the vehicle trim, maintenance can be performed on the sensor without effecting such alignment. The sensor housing is mounted to the interior vehicle trim, door panel, and/or door sheet metal and ensures consistent mounting regardless of interior trim or factory installation variations. In addition, integral adjustment mechanisms are incorporated in further embodiments to provide the ability to make adjustments in either an initial installation environment or after the vehicle is fielded. In yet another embodiment, the circuit board is comprised of plural subsections interconnected by flexible circuit board, enabling accurate alignment of each subsection with respect to the environment to be monitored. Thus, accurate installation is realized through features which locate the housing relative to the vehicle sheet metal or some other consistent reference surface, through adjustment tools associated with the housing which it is installed, or both.